Stapling machine



y 5, 1970 c. o. LARSON 3,510,043

STAPLING MACHINE Filed May 22, 1967 5 Sheets-Sheet l [.VVENTOR.

CHARLES 0. LARSON y 1970 c. o. LARSON 3,510,043

STAPLING MACHINE Filed May 22. i967 s Sheets-Sheet 2 5 FIG. 6 39 y 1970 c. o. LARSON 3,510,043

STAPLING MACHINE Filed May 22. 1967 3 Sheets-Sheet 5 United States Patent 3,510,043 STAPLING MACHINE Charles 0. Larson, Sterling, Ill., assignor to Chas. 0. Larson, (30., Sterling, 11]., a corporation of Illinois Filed May 22, 1967, Ser. No. 640,277 Int. Cl. B25c /06 US. Cl. 227-113 11 Claims ABSTRACT OF THE DISCLOSURE A stapling machine for gravity feeding and driving U-shaped staples of various sizes, the machine including a block having a staple receiving chamber therein and a plunger operatively associated with the block for 1ongitudinal reciprocatory movement relative thereto between a staple driving position and a staple receiving position; a staple holding magazine is carried by the block and includes an elongated slide therein having a discharge end adjacent to the staple receiving chamber; the slide has a cross section that accommodates sliding movement therealong of U-shaped wire staples of various sizes to the staple receiving chamber in the block. An outer surface of the slide facing the bights of the associated staples is disposed adjacent to the plunger and inclined at an angle of substantially about 45 with respect to the direction of movement thereof thereby to provide gravity feeding of the staples to the staple receiving chamber during the use of the machine for driving staples in both the horizontal and vertical directions. A magnetic member may be disposed in the block to urge the staples along the slide and hold the lead staple in a driving position in the staple receiving chamber. The block has a groove in one end thereof and a rotatable dial partially overlying the groove, the dial having a plurality of circumferentially spaced notches therein, whereby the stapling machine may be placed over elongated articles having cross sections complementary to the notches for stapling the articles to an underlying support surface.

This invention relates to stapling machines, and more particularly, to a stapling machine particularly useful for stapling ground cover wires to utility poles, or the like.

A primary object of the invention is to provide a stapling machine for gravity feeding U-shaped wire staples and for driving thereof in both the horizontal and vertical directions.

Another object of the invention is to provide a stapling machine capable of feeding and driving U-shaped wire staples of various sizes in both the horizontal and vertical directions.

Yet another object of the invention is to provide a stapling machine for use in stapling elongated semi-circular ground cover wires of various diameters to underlying support surfaces.

In one aspect of my invention there is provided a stapling machine for gravity feeding U-shaped wire staples and for driving thereof in both the horizontal and vertical directions.

The machine comprises a block having a staple receiving chamber therein, and a plunger operatively associated with the block for longitudinal reciprocatory movement relative thereto between a staple receiving position, wherein the plunger is disposed closely adjacent to the staple receiving chamber, and a staple driving position, wherein the plunger is in driving contact with an associated staple for driving thereof from a staple receiving chamber. A staple holding magazine is carried by the block and includes an elongated slide having a discharge end adjacent to the staple receiving chamber, The slide has a cross section accommodating U-shaped wire staples with the outer surface of the slide positioned in use towards the 3,510,043 Patented May 5, 1970 bights of the associated staples, whereby the slide accommodates sliding movement therealong of the staples to the staple receiving chamber in the block. The outer surface of the slide is disposed adjacent to the plunger and is inclined at an angle of substantially about 45 with respect to the direction of driving movement thereof, whereby the slide provides gravity feeding of staples to the staple receiving chamber during use of the machine for driving staples in both the horizontal and vertical directions.

Further features of the invention pertain to the particular arrangement of the elements of the stapling machine, whereby the above-outlined and additional operating features thereof are attained.

The invention, both as to its organization and method of operation, together with further objects and advantages thereof, will best be understood by reference to the following specification taken in connection with the accompanying drawings, in which:

FIG. 1 is a view in perspective of a stapling machine embodying the invention, and illustrating the position of the stapling machine when driving a staple in the horizontal direction over a ground cover wire;

FIG. 2 is a view in perspective of the stapling machine FIG. 1, illustrating the position thereof when the stapling machine is used to drive staples in the vertical direction;

FIG. 3 is an enlarged side elevational view of the stapling machine shown in FIG. 2;

FIG. 4 is a front elevational view of the stapling machine as seen in the direction of the arrows along the line 4-4 of FIG. 3;

FIG. 5 is a cross sectional rear view taken in the direc tion of the arrows along the line 55 of FIG. 3;

FIG. 6 is a fragmentary plan view of the stapling machine of FIG. 3 as seen in the direction of the arrows along the line 6-6 of FIG. 3;

FIG. 7 is a partially exploded view on a reduced scale of the stapling machine of FIGS. 1 through 3, illustrating various details thereof;

FIG. 8 is a view in vertical section of the stapling machine of FIG. 3 taken in the direction of the arrows along the line 88 of FIG. 5, illustrating the stapling machine in greater detail;

FIG. 9 is a sectional view of the stapling machine taken in the direction of the arrows along the line 9-9 of FIG. 8, illustrating the cross section of the staple magazine and associated slide in greater detail;

FIG. 10 is a sectional view taken in the direction of the arrows along the line 1010 of FIG. 8, illustrating the relationship of the staple magazine to the stapling machine; and

FIGS. 11 through 14, inclusive, are views illustrating the relationship of the cross sections of the slide to staples of various sizes positioned thereon.

Referring now to the drawings, and more particularly to FIGS. 1 through 3, there is illustrated a stapling machine generally designated by the numeral 20. As seen in FIG. 1, the stapling machine of the present invention may be advantageously employed for stapling an elongated cover 21 which shields a ground wire 22, to an underlying support surface or pole 23.

The stapling machine 20 generally comprises a block 30 having a staple receiving chamber 30A (FIG. 8) therein adapted to receive a staple 40. A plunger 50 is operatively associated with the block 30 for longitudinal reciprocatory movement relative thereto, as described in greater detail hereinafter. The stapling machine 20, further includes a staple holding magazine 60 carried by the block 30 and including an elongated slide 70 having a discharge end 71 adjacent to the staple receiving chamber 30A.

As'best seen in- FIG. 8, the slide 70 is positioned in use so that anouter surface 72 thereof faces the bights 41 of the associated staples 40, whereby the slide 70 accommodates sliding movement therealong of the staples 40 to the staple receiving chamber 30A.

Referring now to FIGS. 7 and 8, wherein the block 30 and the staple magazine 60 are shown in greater detail, the bloclc 30 is seen to comprise a feed plate 31 having a rectangular notch 32 therein, the notch 32 in plate 31 being in alignment with the discharge end 71 of the slide 70. The notch 32 divides the feed plate 31 into two spacedapartlparallel legs 31A joined by a crown portion 31B,

whereby the notch32 accommodates passage of the U- shaped staples 40 through the feed plate 31. A pair of laterally spaced-apart generally rectangular guide members 33 overlie the feed plate 32 on the side thereof opposite thestaple magazine 60; each of the guide members 33 being coextensive in width to the respectively adjacent leg 31A of the feed plate 31 and extending over the full height thereof. The opposed inside walls 33A of the guide members 33 define a pair of parallel side walls of the staple receiving chamber 30A.

Each of the guide members 33 has a tongue 34 extending inwardly therefrom disposed parallel to the feed plate 31 and partially overlying the notch 32. Each of the tongues 34 is spaced from the feed plate 31 a distance substantially equal to the thickness of the wire of the largest size staple which the stapling machine is designed to accommodate. The tongues 34 cooperate to define a rear wall for the staple receiving chamber A, so that upon passage of a staple 40 through the notch 32, the legs 42 of the adjacent staple abut the respectively adjacent ones of the tongues 34 whereby the staple 40 is positioned in the staple receiving chamber 30A. It will, therefore, be understood that the staple receiving chamber 30A is defined by the feed plate 31, the sides 33A of guide members 33 and the rear wall defined by the tongues 34, as partially seen in FIG. 8.

An end plate overlies the guide members 33 and is disposed parallel to the feed plate 31. The end plate 35, the guide members 33 and the feed plate 31 cooperate to define a longitudinally extending channel therebetween adapted to receive the plunger 50 for longitudinal reciprocatory movement relative thereto.

Still referring to FIGS. 7 and 8, it will be seen that the plunger 50 has a pair of grooves 51 provided therein, one of the pair being disposed on each side of the plunger adjacent the side walls 33A of guide members 33, the grooves 51 permitting the plunger 50 to cooperate with the corresponding tongues 34 of the guide members 33 for reciprocatory movement thereover.

The plunger 50 is adapted to reciprocate in the channel within .the block 30 between a staple receiving position, wherein the plunger is disposed closely adjacent to the staple receiving chamber 30A (slightly above the position of the plunger 50 as shown in FIG. 8), and a staple driving position, wherein the plunger 50 is in driving contact with an associated staple for driving thereof from the staple receiving chamber 30A (well below the position of the plunger 50 asshown in FIG. 8).

The surface of the plunger 50 between the grooves 51 and the side thereof adjacent to the feed plate 31 comprises a drive area 52 that is coextensive with'the staple receiving chamber 30A, so that upon movement of the plunger 50 toward the staple driving position, the drive area 52 thereof engages the staple disposed in the staple receiving chamber 30A and effects discharge thereof through the bottom of the block as viewed in FIG. 8.

To complete the description of the block 30, it will be best'seen' in FIG. 7 that the end plate 35 has an elongated slot 36 therein extending in a direction parallel to the driving movement of the plunger 50. The plunger has a-pin 53 projecting therefrom which, when the block 30 is assembled, projects into the slot 36,-whereby the ends of the slot 36 cooperate with the pin 53 to limit the longi- 4 tudinal movement of the plunger 50 with respect to'the block 30, for reasons hereinafter explained.

The end plate 35 has a semi-circular notch 37 therein in alignment with the notch 32 in plate 31, whereby the notches 32 and 37 and the space between the guide members 33 and the tongues 34 cooperate to define a groove 38 (FIG. 4) in the end of the block 30. The groove 38 is disposed transversely of the staple receiving chamber 30A and normal to the longitudinal axis of the plunger 50, whereby the block 30 may be placed over an article shaped complementary to the groove for stapling of the article to an underlying support surface.

The stapling machine 20 further includes means for constantly biasing the plunger downwardly, such as the spring 54 that extends between a first eye-bolt 55 disposed adjacent the end of the plunger 50, and a second eye-bolt 56 that is threaded into the end plate 35. The spring 54 biases the plunger 50 toward its staple driving position, whereby the plunger 50 is adapted snugly to abut the bight 41 of an associated staple 40 disposed in the staple receiving chamber 30A, during use of the stapling machine 20 for driving staples in both the horizontal and vertical directions.

To assemble the block 30, screws 39 are adapted to be threaded into the aligned openings 39A provided in the end plate 35', the guide members 33 and the feed plate 31.

As heretofore mentioned, one of the primary objects of the invention is to provide a stapling machine capable of feeding and driving staples of various sizes. To this end slide 70 having the particular cross-section shown in FIGS. 10 through. 14, is provided which, when disposed in a direction parallel to the driving movement of the plunger 50 accommodates the U-shaped wire staples of various sizes.

The slide 70 includes an outer surface 72 positioned in use toward the bights 44 of the associated staples 40, and a pair of guide surfaces 7.3 respectively positioned in use adjacent to the outer ends of the legs 42 of the associated staples 40. The outer surface 71 has a width slightly less than the distance between the legs 42 of the smallest staples to be held in the magazine 60, and the guide surfaces 73 diverge outwardly with respect to the outer surface 72 thereby to guide the outer ends of the legs 42 of all sizes of staples held in the magazine 60.

Thestaples most frequently used for stapling ground cover wires to underlying support surfaces are of the following sizes: 2" x /2"; 1% x /2"; 1 /2" x 1%" x and 1" x A", respectively illustrated in FIGS. 10-14 inclusive, the large dimension represents the height of the staple from the tip of the legs 42 to the top of the bight 41, and the smaller dimension represents the distance between the legs 42 of the staple. To accommodate staples of the various dimensions stated, the outer surface 72 of the slide must be substantially about /4" in width. The full height of the discharge end 71 of the slide is approximately 1 and the guide surfaces 73 extend from a point spaced about /2" below the outer surface 72 and diverge outwardly therefrom at an angle of substantially about 9 relative to a longitudinal plane normal to the outer surface 72 as viewed in FIGS. 10-14. The foregoing dimensions are representative of a cross section of the slide 70 taken in a plane parallel to the discharge end 71. As seen in FIGS. 10 through 14, a slide 70 constructed in accordance with these parameters will readily accommodate staples of the various sizes heretofore mentioned, as well as staples of intermediate sizes. The staple magazine 60 includes an elongated housing 61 disposed around the elongated slide 70, and as shown in FIGS. 2, 5 and 7, the housing 61 may comprise two U- shaped channel members, 62 and 63, the legs of one of the channel members overlying the legsof the other. The channel members may be secured to each other by any suitable means such as the screws 64.

The inner surface of the housing 61 adjacent the outer surface 72 of the slide 70 is spaced therefrom a distance only slightly greater than the thickness of the largest staple to be disposed in the staple magazine 60, the housing 61 thereby serving to hold the staples 40 in the operative position on the slide 70 when driving staples in both the horizontal and vertical directions.

As seen in FIGS. 8 and 9, the screws 64 used to hold the channel members 62 and 63 together may also be used for securing the slide 70 within the staple magazine 60, as shown in FIGS. 8 and 9.

As seen in FIGS. and 7, the discharge end 71 of the slide 70 and the ends of the channel members 62 and 63 disposed immediately therebelow are respectively provided with aligned grooves 74, 62' and 63' therein, corresponding to the groove 38 provided in the bottom of block 30, whereby the staple magazine 60 and the slide 70 are also adapted to straddle an elongated member such as the cover 21 as shown in the drawings.

The staple magazine 60 is secured to the block by the angle brackets 65 disposed on either side of the mag azine 60 and secured to the feed plate 31 of block 30 and the magazine 60 by screws 66.

Each of the channel members 62 and 63 is preferably provided with a series of slots 67 in the center sections thereof, which slots permit visual observance of the staples in the staple magazine 60, for purposes of loading, etc.

As seen in FIGS. 3 and 8, the outer surface 72 of the slide when secured to the block 30 is disposed adjacent to the plunger 50 and is inclined at an angle of substantially about with respect to the direction of the driving movement thereof. As seen in FIGS. 1 through 3, positioning the slide at this angle permits gravity feeding of the staples 40 to the staple receiving chamber 30A during use of the stapling machine 20 for driving staples in both the horizontal and vertical directions.

To urge the staples into the staple receiving chamber 30A and also to hold the first staple disposed in the chamber in the proper position for impact by the driving area 52 of the plunger 50, the tongues 34 are made of a magnetic material, whereby when the plunger is raised to its staple receiving position, the magnetic tongues attract the staples 40 thereto and the lead staple in the magazine is snapped into the driving position in the staple receiving chamber 30A.

One of the stated objects of the invention is to provide a stapling machine capable of stapling covers of various sizes to their underlying support surfaces. To accomplish this objective, a dial 80 is rotatably mounted about the eye-bolt in a plane parallel to the end plate 35. The dial 80 is provided with a plurality of semi-circular notches, 81 through 84, circumferentially spaced about the periphery thereof. The diameters of the covers most frequently used are A"; A and /2", and accordingly, the semi-circular notches 81 through 84 may have diameters corresponding to these sizes. Thus, the notch 81 may be of a diameter of A", notch 82 of a diameter of notch 83 a diameter of and notch 84 of a diameter of /2". The dial is disposed on the block at a height such that upon selective rotation thereof the selected semi-circular notch partially overlies the semi-circular notch 37 in the end plate 35. It will, of course, be understood that the notch 37 in the end plate 35 is of a slightly larger diameter than the notch 84 in the dial 80 thereby to insure that the notch 37 will not interfere with the positioning of the block 30 over a cover corre sponding in diameter to the largest notch 84 in the dial 80. The staples 40 are preferably provided in a strip that facilitates feeding thereof into the staple magazine 60. The strip comprises a plurality of the U-shaped wire staples 40 adhesively secured to one another such as by a resin coating and each including a bight 41 and a pair of legs 42 disposed in a plane, the midpoint of the inner surfaces of the bights 41 of the staples 40 being in longitudinal alignment and all lying in a common plane. The planes of the legs 42 of the staples 40 are all disposed at an angle of approximately 45 with respect to the common plane containing the midpoints of the inner surfaces of the bights 41, whereby the strip of staples appears to be canted at a 45 angle, corresponding to the inclination of the slide.

In use, the stapling machine 20 is loaded by inserting a strip of the staples 40 of the selected size into the magazine 60. The 45 inclination of the slide 70 causes the strip of staples to be gravity fed down the slide until the lead staple is adjacent to the plunger. Because the plunger is spring biased, it will normally be disopsed in the staple driving position (not shown) wherein the driving area 52 on the bottom thereof is disposed within the staple receiving chamber 30A. To cock the stapler, the plunger 50 is raised upwardly to its staple receiving position. The magnetic tongues 34 are then able to snap the first staple 40 of the strip of staples into the staple receiving chamber 30A. It will, of course, be understood that the tension of the spring 54 is not sufiicient to break the adhesive bond between the staples and to overcome the magnetic attraction of the tongues 34 on the staple 40, which thereby precludes the spring 54 from prematurely forcing the plunger 50 to its staple driving position. If the stapling machine 20 is to be used to staple an elongated ground wire cover, then the dial is rotated to the position corresponding to the diameter of the cover to be stapled, whereupon the block may be placed in a straddling position over the elongated cover 21. The semi-circular notches 81 through 84 in the dial 80 will center the block over the cover 21, and assuming that the proper size staples have been selected, the legs 42 thereof will straddle the elongated cover 21 as shown in FIGS. 5 and 10. The plunger may then be struck at the outer end thereof by means of a hammer or the like, thereby to effect movement of the plunger in the driving direction and against the staple 40 positioned in the staple receiving chamber 30A, and thereby driving the staple 40 into the underlying support 24.

In order to prevent damage to the ground wire cover 21, the plunger pin 53 cooperates with the end of the slot 36 to limit the driving movement of the plunger 50 so that the staple 40 will not be driven completely into the underlying support surface.

Upon raising the plunger for the next stapling operation, the strip of staples, because of the inclination of the slide 70, is once again gravity fed toward the staple receiving chamber 30A, with the magnetic tongues 34 once again attracting and holding the lead staple in position for the next stapling operation.

It will be seen from the foregoing that there is provided a stapling machine for gravity feeding and driving of U-shaped Wire staples in both the vertical and horizontal directions. Moreover, the invention as disclosed herein permits the user to select various size staples for use in the stapling machine, and also permits the stapling machine to be used for stapling a number of different size ground cover wires into their underlying surface.

While there has been described what is at present considered to be the preferred embodiment of the invention, it Will be understood that various modifications may be made therein, and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. A stapling machine for gravity feeding of U-shaped wire staples and for driving thereof in both the horizontal and vertical directions, said machine comprising a block having a staple receiving chamber therein, a plunger operatively associated with said block for longitudinal reciprocatory movement relative thereto and between a staple receiving position, wherein said plunger is disposed closely adjacent to said staple receiving chamber, and a staple driving position, wherein said plunger is in driving contact with an associated staple for driving thereof from said staple receiving chamber, a staple holding magazine carried by said blocks and including an elongated slide having a discharge end adjacent to said staple receiving chamber, a magnet fixedly disposed in said block permanently adjacent to the discharge end of said slide for holding the adjacent staple in the driving position in said staple receiving chamber when said stapling machine is used for stapling in both the vertical and horizontal directions, said slide having a cross section accommodating U-shaped wire staples with the outer surface of said slide positioned in use toward the bights of the associated staples whereby said slide accommodates sliding movement therealong of the staples to said staple receiving chamher in said block, said outer surface of said slide being disposed adjacent to said plunger and inclined at an angle of substantially about 45 with respect to the direction of driving movement thereof, whereby said slide provides gravity feeding of staples to said staple receiving chamber during the use of said machine for driving staples in both the horizontal and vertical directions.

2. The stapling machine set forth in claim 1, wherein said block has a groove in one end thereof disposed transversely of said staple receiving chamber and normal to the longitudinal axis of said plunger, whereby said block may :be placed over an elongated article shaped complementary to said groove for stapling of the article to an underlying support surface.

3. The stapling machine set forth in claim 1, wherein said block has an elongated slot therein extending in a direction parallel to the driving movement of said plunger and said plunger has a pin projecting therefrom into said slot, the ends of said slot cooperating with said pin to limit the longitudinal movement of said plunger with respect to said block.

4. The stapling machine set forth in claim 1, and further comprising means constantly biasing said plunger toward said staple driving position, whereby said plunger is adapted snugly to abut the bight of an associated staple disposed in said staple receiving chamber during use of said machine for driving staples in both the horizontal and vertical directions.

5. The stapling machine set forth in claim 1, wherein said magazine includes an elongated hollow housing disposed around said elongated slide, the inner surface of said housing adjacent said outer surface of said slide being spaced therefrom a distance only slightly greater than the thickness of the bights of associated staples to be disposed in said magazine, thereby to hold staples in the operative position on said slide when driving staples in both the horizontal and vertical directions.

6. A stapling machine for feeding and driving U- shaped wire staples of various sizes in both the horizontal and vertical directions, said machine comprising a block having a staple receiving chamber therein, a plunger operatively associated with said block for longitudinal reciprocatory movement relative thereto between a staple receiving position, wherein said plunger is disposed closely adjacent to said staple receiving chamber, and a staple driving position, wherein said plunger is in driving contact with an associated staple for driving thereof from said staple receiving chamber; a staple holding magazine carried by said block and including an elongated slide having a discharge end adjacent to said staple receiving chamber, said slide having a cross section in a direction parallel to the driving movement of said plunger accommodating U-shaped wire staples thereon and including an outer surface positioned in use toward the bights of the associated staples and a pair of guide surfaces respectively positioned in use adjacent to the outer ends of the legs of the associated staples, said outer surface having a width slightly less than the distance between the legs of the smallest staple to be held in said magazine, said guide surfaces diverging outwardly with respect to said outer surface for guiding the outer ends of the legs of all sizes of staples held in said magazine, and means urging the staples in said magazine toward said staple receiving chamber in said block.

7. The stapling machine set forth in claim 6, wherein said outer surface of said slide is disposed adjacent to said plunger and is inclined at an angle of substantially about 45 with respect thereto in the direction of driving movement thereof, whereby the inclination of said slide permits gravity feeding of said staples to said staple receiving chamber during use of said staple machine for driving staples in :both the horizontal and vertical directions.

8. The stapling machine set forth in claim 6, wherein said means biasing the staples into said staple receiving chamber comprises a magnetic member disposed in said block, whereby said magnetic member holds a staple in position in said staple receiving chamber when said stapling machine is used for stapling in both the vertical and horizontal directions.

9. The stapling machine set forth in claim 6, wherein said slide in cross sections parallel to said discharge end is shaped such that said outer surface of said slide is substantially about A in width, the height of said slide is substantially about 1%", and said guide surfaces each begin to diverge outwardly substantially about /2" removed from said outer surface at an angle of substantially about 9 relative to a longitudinal plane disposed normal to said outer surface.

10. The stapling machine set forth in claim 9, wherein said block further comprises a dial rotatably mounted thereon in a plane parallel to the longitudinal axis of said plunger, said dial having a plurality of semi-circular notches of various diameters circumferentially spaced about the periphery thereof, and said block has a groove in one end thereof disposed transversely of said staple receiving chamber and normal to the longitudinal axis of said plunger, said groove terminating immediately adjacent said dial and having a cross section larger than the largest one of said notches in said dial whereupon rotation of said dial so that a selected one of said notches overlies said groove, said block may be placed over an elongated semi-circular article corresponding in diameter to said notch whereby said notch centers said block over said article for stapling thereof.

11. A stapling machine for gravity feeding of U-shaped wire staples and for driving thereof in both the horizontal and vertical directions, said machine comprising a block having a staple receiving chamber therein, a plunger operatively associated with said block for longitudinal reciprocating movement relative thereto and between a staple receiving position, wherein said plunger is disposed closely adjacent to said staple receiving cham her, and a staple driving position, wherein said plunger is in driving contact with an associated staple for driving thereof from said staple receiving chamber, a staple holding magazine carried by said block and including an elongated slide having a discharge end adjacent to said staple receiving chamber, said slide having a cross section in a direction parallel to the driving movement of said plunger accommodating U-shaped wire staples thereon and including an outer surface positioned in use toward the bights of the associated staples and a pair of guide surfaces respectively positioned in use adjacent to the outer ends of the legs of the associated staples, said outer surface having a width slightly less than the distance between legs of the smallest staple to be held in said magazine, and said guide surfaces diverging outwardly with respect to said outer surface for guiding the outer ends of the legs of all sizes of staples held in said magazine, said outer surface of said slide being disposed adjacent to said plunger and inclined at an angle of substantially about 45 with respect to the direction of driving movement thereof, whereby said slide provides gravity feeding of staples to said staple receiving chamber during the use of said machine for driving staples in both the horizontal and vertical directions, a magnet disposed in said block adjacent to the discharge end of said slide for holding the adjacent staple in the driving position in said staple receiving chamber when said stapling machine is used for stapling in both the vertical and horizontal directions, a dial rotatably mounted on said block in a plane parallel to the longitudinal axis of said plunger and having a plurality of semicircular notches of various diameters circumferentially spaced about the periphery thereof, and said block 10 having a groove in one end thereof disposed transversely of said staple receiving chamber and normal to the longitudinal axis of said plunger, said groove terminating immediately adjacent said dial and having a cross section larger than the largest one of said notches in said dial whereupon rotation of said dial so that a selected one of said notches overlies said groove, said block may be placed over an elongated semi-circular article 10 corresponding in diameter to said notch whereby said notch centers said block over said article for stapling thereof.

References Cited UNITED STATES PATENTS 223,252 1/1880 Smyth 227113 327,537 10/1885 Dodsworth 227147 XR 2,511,795 6/1950 Cote 20656 2,618,779 11/1952 Byard 227--147 XR FOREIGN PATENTS 2,180 1891 Great Britain 213,151 2/1958 Australia.

15 GRANVILLE Y. CUSTER, JR., Primary Examiner US. Cl. X.R. 227-109 

